261434961 has 18 divisors (see below), whose sum is σ = 380836482. Its totient is φ = 172821600.

The previous prime is 261434947. The next prime is 261434981. The reversal of 261434961 is 169434162.

261434961 is a `hidden beast` number, since 2 + 614 + 34 + 9 + 6 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 177822225 + 83612736 = 13335^2 + 9144^2 .

It is not a de Polignac number, because 261434961 - 2¹³ = 261426769 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (261434941) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 144261 + ... + 146061.

Almost surely, 2^261434961 is an apocalyptic number.

It is an amenable number.

261434961 is a deficient number, since it is larger than the sum of its proper divisors (119401521).

261434961 is a wasteful number, since it uses less digits than its factorization.

261434961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2061 (or 1931 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 261434961 is about 16168.9505225293. The cubic root of 261434961 is about 639.4224615685.

The spelling of 261434961 in words is "two hundred sixty-one million, four hundred thirty-four thousand, nine hundred sixty-one".